Eco-friendly process for preparation of biodiesel from WFO over MTSA-Si catalyst: An innovative approach for the utilization of side product

Artificial Neural Network and Response Surface Methodology for Predicting and Maximizing Biodiesel Production from Waste Oil with KI/CaO/Al2O3 Catalyst in a Fixed Bed Reactor

Biodiesel from waste oil is produced using heterogeneous catalyzed transesterification in a fixed bed reactor (FBR). Potassium iodide/calcium oxide/alumina (KI/CaO/Al2O3) catalyst was prepared through the processes of calcination and impregnation. The novel catalyst was analyzed with X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometer (EDX). The design of experiment (DoE) method resulted in a total of 20 experimental runs. The significance of 3 reaction parameters, namely catalyst bed height, methanol to waste oil molar ratio, and residence time, and their combined impact on biodiesel yield is investigated. Both the artificial neural network (ANN) based on artificial intelligence (AI) and the Box-Behnken design (BBD) based on response surface methodology (RSM) were utilized in order to optimize the process conditions and maximize the biodiesel production. A quadratic regression model was developed to predict biodiesel yield, with a correlation coefficient (R) value of 0.9994 for ANN model and a coefficient of determination (R2) value of 0.9986 for BBD model. The maximum amount of biodiesel that can be produced is 98.88 % when catalyst bed height is 7.87 cm, molar ratio of methanol to waste oil is 17.47 : 1, and residence time is 3.12 h. The results of this study indicate that ANN and BBD models can effectively be used to optimize and synthesize the highest %yield of biodiesel in a FBR.

Producción de acetinas (aditivos para combustibles) a partir de glicerol

La elevada producción de glicerol, un subproducto de bajo costo proveniente de la industria del biodiésel, ha supuesto una amenaza tanto para el medio ambiente como para la economía. La transformación de glicerol en productos de valor agregado contribuiría positivamente a la economía del biodiésel. En este artículo de revisión se describen las rutas de valorización del glicerol y se presenta la esterificación como una de las más prometedoras para la transformación de glicerol en aditivos para combustibles; igualmente, se describen los resultados más relevantes entre 2010 y 2020 relacionados con las condiciones experimentales (temperatura, relación molar y tiempo de reacción), los catalizadores heterogéneos y la actividad catalítica (en términos de la conversión del glicerol y la selectividad) para la transformación de glicerol en acetinas (monoacetina, diacetina y triacetina). Se espera que esta revisión permita abordar esta técnica de valorización de manera rentable y ambientalmente sostenible.

Highly efficient synthesis of biodiesel catalyzed by a cellulose@hematite-zirconia nanocomposite

The depletion of fossil fuels calls for the development of renewable alternatives such as biodiesel and has inspired much research on catalysts for the production of biodiesel through the esterification of biomass-derived materials. Herein, a green heterogeneous catalyst for highly efficient biodiesel synthesis was fabricated from rice straw-derived cellulose, hematite, and zirconia and was shown to contain porous irregularly shaped α-Fe2O3-ZrO2 composites (average particle size = 42.5 nm) evenly distributed on the nanocellulose surface. The optimal catalyst (nanocellulose:α-Fe2O3-ZrO2 = 2:1, w/w) afforded biodiesel in a yield of 92.50% and with specifications close to those prescribed by international standards. This catalyst could be reused for up to five cycles without a marked activity loss, with the biodiesel yield in the fifth cycle equaling 80.0%. The developed nanocomposite holds great promise for cutting the costs of biodiesel production, as it is derived from biodegradable raw materials and is renewable, non-corrosive, easy to handle, and green. In addition, the large-scale discharge of this catalyst after use does not pose a hazard to the environment.